1. Field of the Invention
This invention refers to an adjustable mechanism, which primarily is intended to make it possible to adjust the inclination of the seat back of a motor vehicle seat but which also may be utilized in other connections.
2. Description of the Prior Art
A plurality of mechanisms for adjusting the inclination of the seat back of a motor vehicle seat are known. However, these known structures often have the disadvantage that they are complicated and hence expensive to manufacture. Furthermore, they may become defective in use, and thereby they do not fulfil the requirements of stability and the increasingly severe safety regulations, respectively, which are successively being established in various countries.
As an example of a mechanism of known type, mention may be made of the subject of invention of British Patent Specification No. 1,091,994, in which two gears, one having external teeth and the other having internal teeth, are made to mesh with each other. According to the solution provided by said British patent specification, one of the gears is mounted in such manner that it performs an eccentric movement with regard to the other gear, resulting in a relative rolling movement of the two gears so as to make the seat back of the motor vehicle seat move upwards and downwards, respectively, when the seat back is adjusted. Furthermore, the substantial number of components requiring accuracy in the British mechanism results in this mechanism being expensive to manufacture.